It is known to treat urinary incontinence by injecting a viscous biocompatible material such as collagen transcystoscopically into the patient's periurethral tissues. The collagen is injected into the submucosal tissues of the urethra and/or bladder neck, and into the tissues adjacent to the urethra. The injection of the collagen creates increased tissue bulk, thereby exerting a coaptive pressure against the urethra. After injection the suspended collagen forms a soft, cohesive network of fibers, and over time the collagen takes on the appearance of normal host tissue.
The collagen can be implanted into the patient either periurethrally or transurethrally. According to the periurethral injection procedure, a needle is advanced through the perineum parallel to the urethra until the needle tip is located in the desired area for injection. Location of the needle tip is verified cystoscopically by observing the movement of adjacent tissue during gentle movement of the needle. When the needle tip is properly positioned, collagen is injected submucosally until tissue bulking closes the lumen across the midline of the urethral opening. The needle is then withdrawn from the initial injection site, and the procedure is repeated at a location directly across the urethra from the initial injection site. Collagen is injected until urethral closure is observed through the cystoscope, or until a maximum of 30 cc of collagen has been injected.
According to the transurethral procedure, a cystoscope is introduced into the patient's urethra. A catheter having a needle at its forward end is advanced through the working channel of the cystoscope to the desired area for injection. The needle is then advanced into the urethral wall, and collagen is injected submucosally until tissue bulking closes the lumen across the midline of the urethral opening. The needle is then withdrawn from the initial injection site and advanced into other locations on the urethral wall as needed. Material is injected at these other locations until urethral coaptation is observed through the cystoscope, or until the maximum of 30 cc of collagen has been injected.
Occasional problems arise in both the periurethral and transurethral injection procedures. On certain occasions it may require injection of an unexpectedly high volume of collagen to attain coaptation. On other occasions, even where coaptation of the urethra is achieved during the procedure, it has been found that on certain occasions within twenty-four to forty-eight hours after the procedure coaptation is not maintained. Additional injections of collagen may then be required to augment the initial injections to reattain coaptation. Such additional injections result in increased patient discomfort, cost, and patient morbidity.
Thus there is a need for an improved apparatus and method for injecting collagen or other suitable viscous biocompatible material into the periurethral tissues as a treatment for urinary incontinence.
There is a further need for an improved apparatus and method for periurethral and transurethral injection of collagen or other suitable viscous biocompatible material which affords coaptation while minimizing the volume of collagen which must be injected.
There is a still further need for an improved apparatus and method for periurethral and transurethral injection of collagen or other suitable viscous biocompatible material which maintains coaptation of the urethra once achieved.